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FORUM

Trimming capacitors

Semtech Transceivers SX126x family
#1

Hi,

There is information in SX1261/2 documentation that trimming capacitors settings will be overwritten by state machine when entering STDBY_XOSC mode.

My question is, how chip behaves when I’m skipping STDBY_XOSC mode by waking-up to STDBY_RC mode and switching directly to TX or RX? Is it going through STDBY_XOSC state under the hood or not?

In such scenario how should I set trimming capacitors? Switch to STDBY_XOSC, set capacitors and start TX/RX, or can I set them in STDBY_RC and they won’t be overwritten when starting TX/RX?

Best regards
Tomasz

#2

Yes, it is.

You need first to set the chip in STDBY_XOSC, then update the trimming capacitors to finally set the chip in Tx or Rx.